Messages in this thread | | | Date | Wed, 1 Jun 2005 22:44:30 +0200 | From | Andrea Arcangeli <> | Subject | Re: RT patch acceptance |
| |
On Wed, Jun 01, 2005 at 09:39:06PM +0200, Ingo Molnar wrote: > yes. As i said in an earlier mail: > > > > (there are still some ways to introduce latencies into PREEMPT_RT, > > > but they are not common and we are working on ways to cover them > > > all.) > > local_irq_disable() is one way, preempt_disable() is another way. Adding
btw, I didn't mention preempt_disable because that really is called a pair of times in the whole drivers.
> asm("cli") to your driver is a third way. In practice these items are > not a big issue, so i'm not yet covering them. It's a small detail. > Check the amount of local-irq-disable instances in the driver space vs. > spinlock use.
It's not as frequent like spin_lock_irq, but it's still a relevant driver API (unlike preempt_disable). So I think it worth fixing to really provide the same guarantees as RTAI and rtlinux. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |